It didn't work, unfortunately :( I tried setting it to Read & Write and then I tried Read Only and it still said I didn't have permission for it, which is super weird since this is my personal laptop and I'm the only one who's ever used it
I am doing some research and it seems it's a Mac OS issue, especially users with the Big Sur update. I don't have access to a Mac, so I can not test it with my file specifically. I know others have been able to open the file, but that's all I know. I found a lot of articles/videos related to this issue on Mac, maybe one of them will help you.
Well, I have absolutely no idea what it did, but I ran one of the commands this guy tried (which apparently failed for him) but it worked for me! Thank you so so so much!!!!! So excited to play :)
Edit: just in case anyone has the same issue as me in the future - what i did was paste sudo chmod -R 755 into the terminal, spacebar, and then drag the app into terminal to paste its location in there, then press enter to run it. this let me actually open the app, but THEN it got stuck on the black screen with the hourglass loading in the bottom right corner forever, so what i did next was paste xattr -d com.apple.quarantine into terminal, space, then drag the app into terminal again and press enter. the next time i ran the app it ran properly :)